Internal-combustion-engine cylinder and process of making same



Aug. 3 1926.

A. L. BQEGEHOLD INTERNAL COMBUSTION ENGINE CYLINDER AND PROCESS OF MAKING SAME Original Filed Dec. 14, 1922 Patented Aug. 3, 1926.

UNITED STATES PATENT OFFICE.

ALFRED L. BOEGEHOLD, OF DAYTON, OHIO, ASSIGNOR TO GENERAL MOTORS RESEARCH CORPORATION, OF DAYTON, OHIO, A CORPORATION OF DELAWARE.

INTERNAL-COMBUSTION-ENGINE CYLINDER AND PROCESS OF MAKING SAME.

Original application filed December 14, 1922, Serial No. 606,797. Divided and this application filed December 19, 1924.

The present invention relates to heat exchange vessels, and processes of making them. In the preferred form of embodiment which has been chosen for the purpose of description and illustration, the invention relates particularly to air cooled internal combustion engines cylinders and to processes of securing in permanently effective heat conducting relation to the cylinder, cooling finsof a highly heat conducting metal.

This is a division of my co-pending application, Serial #606797, filed December 14, 1922.

Among the objects of the invention is to increase the economy and elliciency of processes of making such articles and at the same time form an article which is itself more efficient in its functions. I

Another object is the decrease in the number of operations in such processes, thereby shortening the time usuallyconsidered necessary and cutting down the, cost.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had.

to the accompanying drawings, wherein a preferred form ofembodiment of the present invention is clearly shown.

In the drawings:

Fig. 1 illustrates partly in vertical section a cylinder produced by the present process.

Fig. 2 is a vertical section through a mold prepared for the casting operation and having a cylinder barrel and prepared fins set th rein. Fig. 3 1s a horizontal section of Fig. 2, on

line 33.-

Fig. 4: is an enlargement of a portion of Fig. 3.

Fig. 5 is a view similar to Fig. l butillnstrating a modification of the firming method.

The prepared material used in making the present type of cylinder are those mentioned in the specific description immediately following but it should be understood that other materials may be used provided they are suitable for the process and have properties adapting them for the functions which they will have in the finished cylinder.

The cylinder shown in Fig, 1 preferably consists of a steel barrel 10 having a cast on iron base ll. It also shows a hianetallic head consisting; of a cast in plate of iron 12 Serial No. 757,070.

more particularly described later. And be- I tween these fins 14 and barrel 10 is a thin layer of copper 15. p

The bonds between the several portions, when the process is properly carried out are permanent metallic bonds and are efficiently heat conductive, which' property is highly desirable at the, junctionbetwee'n the fin material and the cylinder barrel and head andbetween the. head materials and between these latter and the barrel;

In carrying out the process, a steel tube is set in a suitable mold and an. iron plate of suitable thickness cast in one end thereof in any well known manner so as to produce a welded junction between the two'metals. Such a prepared tub'eis indicated at 10 and 12 in Fig. 2.

A suitable mold is then-prepared, as indicated in Figs'.2 and 3, having embedded in its walls a set of cooling fins l l with their bases projecting into or forming a wall of the mold proper. The mold proper should tion 13.

Around the upper end of the tube there is also formed a second mold 30-for casting base 11.

There are provided also a gate 35 and riser 36 for the lower mold and a gate 37 and riser 38 for the upper mold.

When the molds have been thus prepared with the fins 14; and tube 10 in place, a thin cup of baked core material a0 is placed inside of tube 10 and after runner boxes have been placed thereon as indicated, the mold is ready for. pouring.

The pouring operation is conducted as follows; first molten iron is poured into cup 40 for the purpose of highly heating tube 10 and head portion 12. Then after an interval of a few seconds, to give the tube a chance to get hot, iron for the base 11 is poured in through gate 37 and, immediately llll thereafter, copper is poured :hroua'h :he gate 35.

The tube being thoroughly incl llQ'illY heated, the copper runs in readily and ills space 21 and rises in annular space 20 welding itself to plate 12. fins l4 and tube l0 forming a permanent and effective heat conductive bond.

The cylinder is then removed from the mold cleaned and finished.

2t modification of the process u-st lescrire consists in casting thin cooling llns of the copper at the same time that head is cast, instead of setting previously formed fins in the mold as indicated. In this modification the mold is prepared and the tube 10 po-efiioned therein in the same manner as has been descrloed except that thin :orlns are prepared therein in which the coolin fins are cash sit s ction of a portion or such a iii-old is shown in Fi 1 .n which LO :5 the steel tube the an space and 30 the forms for the cast col i is; lin-s.

\Vhile the forms of embodiment vention as herein shown and descrit .1lstitute preferred forms. ll) is to as 111C161- stood that other forms might be adopted. all

fOIIllDQ VIUHD :he scoDe 01 the claims which hat ;lalln is is :ollo'ws:

The croccss or DIOCUICIIIQ internal coin- )ustion 1121118 -3Vllndrs lllCll comprises setting .1 series or fins in a mold with their nner ends or oases exposed to the interior t the mold: oosltionlna' a cvlluder. provided with a thin aead. within the mold in such ishion as to leave an annular suace between .t and the tin oases and so as to have av space for additional head metal: lining the cylin- WEI: with a DIOEQCUILQ' layer: pouring into the :vlinder molten metal for oreheatiug same: ind casting 1n the annular soace and head mace another metal to min the cvlinder and ans and thicken :hc head.

J. In a orocess or casting cooper cooling elements 'mon :errous metal cvlindcrs. prerieatinrr i118 cvhllder ov lillina 1D with molten ast llOD. :he cvllnoer oeina prevented from moking '0 he .ron )v L :nln protective h :estnnonv whereof I aereto atfix mv denature.

-JRED L. BOEGEHOLD. 

